Device for production of uncured propellant strands

ABSTRACT

A device for uniformly filling plastic straws with uncured propellant to form propellant strands. The device includes a syringe-type device mounted in a housing in alignment with a plastic straw to be filled with propellant. A lever on the housing is used to engage a plunger of the syringe and force propellant within the syringe into the plastic straw to form a propellant strand in which the propellant is uniformly arranged within the straw.

United States Patent Filed Seiford F. Schultz Huntsville;

Andrew B. Nix, Guntersville, both of Ala. 49,704

June 25, 1970 Jan. 1 l, 1972 The United States of America as represented by the Secretary of the Army inventors Appl, No.

Patented Assignee DEVICE F OR PRODUCTION OF UNCURED PROPELLANT STRANDS 8 Claims, 3 Drawing Figs.

Int. Cl B65b 3/12 Field of Search 86/31-33,

1; 92/51, 117 R; 141/20, 250, 284, 31 l, 325, 369; 184/15 A; 102/27 56] References Cited UNITED STATES PATENTS 3,335,765 8/1967 Moonan 141/20 2,886,134 5/1959 Simmons..... 184/15 A FOREIGN PATENTS 802,224 10/1958 Great Britain 141/20 Primary Examiner-Edward J. Earls AnorrieysHarry M. Saragoyitz, Edward J. Kelly, Herbert Berl and James T. Deaton ABSTRACT: A device for uniformly filling plastic straws with uncured propellant to form propellant strands. The device includes a syringe-type device mounted in a housing in alignment with a plastic straw to be filled with propellant. A lever on the housing is used to engage a plunger of the syringe and force propellant within the syringe into the plastic straw to form a propellant strand in which the propellant is uniformly arranged within the straw.

PNENTEU'JW 1 E172 FIG.

Seiford F. Schultz Andrew B. Nix,

FIG. 3

FIG. 2

DEVICE FOR PRODUCTION OF UNCURED PROPELLANT STRANDS BACKGROUND OF THE INVENTION Uncured strands of high-viscosity propellant are used extensively in the quality control of propellant burning rates during the processing stages of rocket motor production. The procedure and apparatus for preparing such strands in the past has required personal handling of the filling syringe in preparing the straws and up to one hour has been required in filling a minimum number of 12 strands. (The time required to prepare the strands is dependent upon the viscosity of the propellant). Therefore, there is a need for a device that is safe and can be used to quickly fill plastic straws to form propellant strands irrespective of the high viscosity of the uncured propellant.

Therefore, it is an object of this invention to provide a device that is safe and can be used to quickly fill a number of plastic straws with uncured propellant.

Another object of this invention is to reduce the hazard of filling plastic straws by eliminating personal handling of loading syringes when under pressure and dispensing the propellant into the plastic straw.

A further object of this invention is to provide a device that can be used to yield more reproducable strands by improving the packing of propellant and reducing voids.

Still another object of this invention is to reduce strand loss during processing by supporting the plastic strawand'thereby preventing breakage of the plastic straw when used with highviscosity propellants.

A still further object of this invention is to reduce the cost of the quality control program by obtaining more data with less propellant material due to practically no propellant material being wasted by the apparatus used in placing the propellant material in the plastic straws.

SUMMARY OF THE INVENTION A device for making uncured strand propellant is provided which includes a body with a syringe-type device mounted in the body for dispensing uncured propellant within the syringe into a plastic straw. The plastic straw is positioned in means in the body that align the straw with one end of the syringe-type device. A lever mounted on the body is used to apply force to a piston of the syringe and force propellant within the syringe into the straw aligned with one end of the syringe.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side view of the device for preparing propellant strands according to this invention.

FIG. 2 is a view taken along line 22 of FIG. 1, and

FIG. 3 is a view taken along line 3-3 of FIG. 1 with the flared tube and plastic straw removed.

DETAILED DESCRIPTION OF THE INVENTION Referring now to FIG. 1, body 1 has rod 3 fixedly secured thereto. Lever arm 5 has end 7 pivotably secured to end 9 of rod 3 by a pin connection 11. Body 1 has bore 13 (see FIG. 2) therein that is tapered at 15 to retain syringe 17 within bore 13. Body 1 is made with grooves 19 and 21 (see FIG. 1) that are perpendicular to groove 23 (see FIG. 3) that is between grooves 19 and 21. Groove 23 is tapered at 25 (see FIG. 2) to receive tube 27 that is flared at 29 to be received in tapered portion 25. A plastic straw 31 is slidably positioned in flared tube 27 with the bottom end of plastic straw 31 spaced from surface 33.

The syringe 17 includes a cylinder portion 35 that has an open end with flange 36 and a reduce diameter end 37 that is tapered. Tip end portion 38 is adapted for telescoping movement into flared tube 27 and plastic straw 31 to wedge plastic straw 31 between the tip end portion and flared tube 27. Piston 39 is mounted in cylinder portion 35 to define chamber 41 in cylinder portion 35. Piston 39 has resilient seal 43 mounted at one end for sealing relative to the cylinder wall of cylinder portion 35. The other end of piston 39 has a flange 45 and a universal connection engaging portion 47 for engaging.

hemispherical member 49 mounted on lever arm 5. Spring 51 is positioned around the syringe with one endof springSl in engagement with flange 36 and theother end of springs 1 in.

engagement with the body. Spring 51v maintains reduced diameter end 37 out of contact with tapered shoulder 15 when no force is being applied to lever 5 by an operator. In this.

from cylinder portion 35. Cylinder portion 35 is then filled with uncured propellant. The piston is now inserted into the cylinder portion and syringe 17 is inserted into bore 13. With flared tube 27 and plastic straw 31- in place, as illustrated in FIG. 2, lever 5 is moved downward to first compress spring 51 until reduced diameter end 37 contacts tapered portion 15 and tip end portion 38 of the reduced diameter end has telescoped into plastic straw 31 and wedged plastic straw 31 relative to flared tube 27. Additional force applied to move lever 5 downward causes piston 39 to force propellant out the. opening in tip end 38 through'the reduced diameter end into plastic straw 31. Air within straw 31 escapes through the bottom of plastic straw 31. When plastic straw 31 is full, lever arm 5 is released and spring 51 retracts the tapered end from plastic straw 31. The propellant strand formed-by the uncured propellant and plastic straw 31 may now be-removed for use by removing flared tube 27 and plastic straw 31 from groove 23 and removing flared tube 27 from plastic straw 31. This same procedure is repeated for preparing the number of strands desired.

Various modifications and variations of this invention will become readily apparent to those skilled in'the art in the light of the above teachings, which modifications and variations are within the spirit and scope of this invention.

We claim:

1. A device for preparing propellant strands, said device comprising: a body; a lever mounted on said body and to one side; a bore in said body and spaced from the mounting for said lever; a syringe mounted in saidbore, said syringe including a cylinder portion that has a reduced diameter at one end and an opposite end that'receives one end ofa piston for linear movement in the cylinder and another end of saidpiston that is adapted to be engaged by said lever to have force applied: to said piston by said lever; and means in the body for supporting a plastic straw in alignment with the reduced diameter end ofsaid cylinder to receive propellant forced'from saidcylinder, said means in said body including a first groove in said body in alignment with said bore and a second groove in' said body between said first groove and said bore and extending perpendicular to said first groove.

2. A device for preparing propellant strands as set forth in claim 1, wherein said mounting means includes a third groove in said body and extending parallel to said second groove, said first groove being between said second and third grooves.

3. A device for preparing propellant strands as set fdrth in claim 2, wherein said mounting means further includes a tube with a flared end, said tube being inserted into said first groove to be in alignment with said bore and with said flared end-of said tube resting on a portion of the body where the first and second grooves intersect.

4. A device for preparing propellant strands as set forth in claim 3, wherein said reduced diameter is in a tapered portion of said cylinder and the smallest outside dimension of said tapered portion is smaller than the opening in said tube to allow said tapered portion to be telescoped into said tube.

5. A device for preparing propellant strands as set forth in claim 4, wherein a universal-type jointisprovided between said lever and said another end of said piston.

6. A device for preparing propellant strands as set forth in :laim 5, wherein said syringe is mounted in said bore with a :pring between a flange at said opposite end of said cylinder )ortion and the body around said bore to allow said cylinder )ortion to move in said bore as force is applied to and released 'rom said piston by said lever.

7. A device for preparing propellant strands as set forth in claim 6, wherein said one end of said piston has a resilient seal. 8. A device for preparing propellant strands as set forth in claim 7, wherein a plastic straw is positioned with one end in said flared tube to have propellant from said syringe forced into said plastic straw. 

1. A device for preparing propellant strands, said device comprising: a body; a lever mounted on said body and to one side; a bore in said body and spaced from the mounting for said lever; a syringe mounted in said bore, said syringe including a cylinder portion that has a reduced diameter at one end and an opposite end that receives one end of a piston for linear movement in the cylinder and another end of said piston that is adapted to be engaged by said lever to have force applied to said piston by said lever; and means in the body for supporting a plastic straw in alignment with the reduced diameter end of said cylinder to receive propellant forced from said cylinder, said means in said body including a first groove in said body in alignment with said bore and a second groove in said body between said first groove and said bore and extending perpendicular to said first groove.
 2. A device for preparing propellant strands aS set forth in claim 1, wherein said mounting means includes a third groove in said body and extending parallel to said second groove, said first groove being between said second and third grooves.
 3. A device for preparing propellant strands as set forth in claim 2, wherein said mounting means further includes a tube with a flared end, said tube being inserted into said first groove to be in alignment with said bore and with said flared end of said tube resting on a portion of the body where the first and second grooves intersect.
 4. A device for preparing propellant strands as set forth in claim 3, wherein said reduced diameter is in a tapered portion of said cylinder and the smallest outside dimension of said tapered portion is smaller than the opening in said tube to allow said tapered portion to be telescoped into said tube.
 5. A device for preparing propellant strands as set forth in claim 4, wherein a universal-type joint is provided between said lever and said another end of said piston.
 6. A device for preparing propellant strands as set forth in claim 5, wherein said syringe is mounted in said bore with a spring between a flange at said opposite end of said cylinder portion and the body around said bore to allow said cylinder portion to move in said bore as force is applied to and released from said piston by said lever.
 7. A device for preparing propellant strands as set forth in claim 6, wherein said one end of said piston has a resilient seal.
 8. A device for preparing propellant strands as set forth in claim 7, wherein a plastic straw is positioned with one end in said flared tube to have propellant from said syringe forced into said plastic straw. 